Swivel joint



P. H. IRMISCHER" May 20, 1941.

.' SWIVEL JOINT Filed Nov.- 24, 1959' INVENTOR w w V 5 mam,

ZZ%J I ATTORN. I

Patented May20,1941 H g a 2 24 2 7 v V 2,242,303 I j f SWIVEL JOINT. I U I Paul H. Irmischer,- Chicagoflll. Application'November 24, 1939, Serial No. 305,801

p fi Claiins. (Cl. 285--97.7) I y h This invention relates to swivel joints for lamp: The improved swivel joint is interided for gen brackets and the like and hasas its rincipal oberal application and has been successniuy em- 'ject the provision of improvedstop-means for. ployed in lamps and'similarfixtu'res in theman limiting the turning movement of the joint ner.illustrated;forexample,in Fig: ,wherein a members'to preventinjury to the electric wiring 5 lampaassembly'j 12 is mounted *ato'ne end of a where the joint is employed in an electric lamp. M bracket armJ3connected by'a. swivel'joint, gen- A' further object is-the provision of improved Y erally indicatedatld, with another'bracket arm stop means arranged to permit the swivel joints to 1 I5 'which inxt'urnnisattached by means of a 'be turned more than one complete, revolution so second swlvel'joint; generally indicated'at, IE, to as 'to provide an amount of,ove'rride, v thus ren- 10 the head of a columnor base postj 11;;11'1 this dering the lamp or other fixture more flexible type of bracketstructureytheelectric conductors while at the same time preventing injury tothe. (not'shown): are carried ,up-tlirough the hollow conductors. Z a v j I r portionsI-laof the'p'ost and througlr'a bore I! in" Viewed from another aspect, it is an object of. I the swiveljoint into the bore l5a,'and on'tl'n'qugh the invention to provide a swivel joint including 15 the'joint Handarm 'I'3.for connection with the a pair ofrelatively rotatable swivel members. 7- lamp [2. i i If with a movable stop element interposed between 'It will be apparent that continued "swinging of the same, and coactingstop means on the swivel; 1 vthe bracket arms relative to the p st will members so arranged that by turning onetim ,eventually rupture the insulationand even the members with respect to theflotherin either diconductors in the type of wireusually'employed motion, the movable stop element will be posij in these devices, if the bracket arms: are rotated tioned for stopping engagement with the stop through several revolutionsin thes'ame'di'rection, means on one or the other of the swivel memit being obvious that this will twist the conductors bers to arrest he turning movement after the r. and exert acpullupon the same resultingfin the swivel members'have been turned a predeter-- destruction ofthe'insulation and the'dangerous mined amount beyond '360 degrees. 1 likelihood of firedue to short circuiting.-

Other objects, advantages and novel aspects 'In order to prevent injury to the conductors. of the invention reside in certain details ,ofconit has been the practice heretofore to provide a struction as well as the cooperative relationship op means O- e' li i wfi :0! e of the component parts of the illustrative embodibracket ar s I nd IS with resp ctf d'fl D s ment described hereinafter in view'of the an-' I?! so that thesame cannot turn :beyond360. de-

nexed drawing, in which:' I greesiop one. complete-revolution. Fig. 1 shows a perspective fragmentof a bridge However, this arrangement has been found ing lamp; a p V co'nvenientin adjusting a lamp to accommodate.

Fig. 2 is anenlarged sectionalong line 2-2 of some particular peculiarity of. its location with Fig. 1 through one of the swivel 'joints, disclosrespect to walls or other pieces of furniture, for ingone type of stops means; it is frequently necessary to turn the base struc- 1 Fig 3 is a horizontal section through the swivel 6 thevlamll n Order 150 diSPOScthB e joint'o'f F 'ig.-2, looking up along line 33; so that the bracketarms may be swung into the .Fig. 4 is a horizontal sectional view. taken 40v desired position. I a 7 through a modified 'form of stop means taken a It has "been found that the electricmonductors along a section line'correspo'nding ,.to linej33 will not be injured if the bracket armsare'perof Fig. 2; a 'mitted to swing beyond 360 degrees, it' being Fig. 5 lsa fragmentary section of a, .modified merelynecessary to prevent continued rotation 7 form of stop means taken along a similar section of the swivel members beyond two or three turns. 1 lineto Figs. 3 and 4; v The present invention provides a'stopr means Fig. 6 is a fragmentary perspective of thestop which will permit the swivel joints" to; turn means of Fig. 5; I through more than one revolution and not more Fig. 7 is a vertical section through a modified thana sa e num e f r p two or t r construction of the swivel joint and stop means; 5 b yO d, t s. obviating the P inconvenience Fig, 8 is across section along line 8-8 of Fig. '7; of having to turn the entire lampstructure or Fig. 29 is a verticabsection through another other fixture in. order to adjust therarms for modified form of swivel joint and stop means; movementla short distance beyond the stopping- Fig. 10 is a cross section alongline "I -l0 of point in a particular direction. I Fig.9. r V Apart from the foregoing advantages, the inwith respecttom'center coinciding'with-thepivvention also'provides a simpliflcd joint construetionwith respectboth to the stop means and means for joining the'swivei members as a unit. In the'embodlment shown'inFigs. 2' and'3, the

swivel joint includes-a lower swivel member 20' threaded upon the upperend of the." column orpost IT, and a companion swivel" member 2| which is rotat'abiyseated in the'flrst member by the provision of a flare or flange portion 22- around the bottom periphery, saidfi'are being cated-at 30. which corresponds to the length. of override, as will be pointed out hereinafter. The terminals ll' and I! constitute stop means on one of the --joint' members, the stop; means. on theother joint member "being-in the nature of a radially extending. slot 31* which; is long enough.

gripped. by turned-over or spun-portions 28 around theitop oi; the" bottomloint member,- the members 20 and being. free toturn' with respent to each other. The central. boreil-a ex tends through both Joint members and, communicates with the bore l'l'a in the bracket I! which is threaded into the upper: joint member 2|. v

The stop means-(Fig.3) includes theprovision in the upper endor face of the lower swivelmember of a groove or track which extends concentrically of the bore II, and hence the pivotalaxis of the swivel members, through a'distance voi less than 360 degrees, the terminal ends 2i" and2l'of this groove constituting stop means'orr the lower swivel member. 2|; these terminal 'ex-' tremities beingseparat'ed by a short intervening otal "axis oi the joint members :through the bore portion llm'the'opposite terminals; or ends SI and or which. are displaced angulariy with respect to said? center by a lengthotiarc indito bridge" the distance'between the terminal; 3|:

0! the outermost convolution and the next adjace'nt convolution along'a radiusirom' the turning axis of the members.

Movable stop means in the nature of abearing:

ball disposed in the spiral and' the shorter radial groove 31 when the joint. members are in assembled relation, and' it will be apparent that :when the swivel joints are turned one with respect to the other, the ball lliwill ride in the spiral groove and shift its position. intheradlal groove 31 as the'rotative movement continues.

*and when a complete revolution has beenmade, 25'- we ball as will be at the pw v of the short groove '31 irornthat shown in Fig. 4, the

carry -over or override beyond acomplete revolution" of360 degrees beingeil'ective in the rebody portion 28 of the swivel member. The' section of Fig. 3 has been taken'inl i'g. "2 along a'- line just below the upper face or end'oi the lower swivel member 20. 3

. Disposed in the groove 25 is a movable stop element in the formota bearin ball 29,-'while the companion orupper swivel member 21 is pro: vided with'a short groove or track 30 also extending concentrically of theturning'axis oi-the j joint members, so that the shorter groove overlies or is in alignment with the-groove or track in the companion membenthe ball "or movable stop means 29 being disposed in both grooves and mainingportion of the spiral groove between its terminal and said inner or opposite end of the groove 31; as seen inFig. 4.. It will therefore be apparent that the spiral groove could be contlnued beyond its innerturn 34 with a. corresponding lengthening otthe groove 31 toward the center to. provide a still greater override.

Another modification, analogous to the arrangement of Fig.4 is shown inFig. 5, wherein a spiral groove 40, in other respects similar to the groove "of Fig. 4, is provided in the lower being adapted to run around the longer groove" a between the ends thereoias'a-result oi the disa placement of the shorter groove, upon turning" of the swivel members. Attention is called'to the fact that the shorter groove 30' is. of a length at least sumcient to-bridge the distance across the intervening body portion 28 between the terminals 26 and 21 of the main or longer groove.

In consequence of the foregoing structural arrangement of long and short grooves, it will be apparent that the ball 28, will becarried against one or the other terminals 26 or '21 when the companion swivel member is turned through nearly 360 degrees. 7

If the shorter groove 30 were'no longer than swivel joint ll, In this arrangement, however, the movable stop means is in the nature of an 7 arm .2 (Fig.6 also) pivoted seat 41 in a slot 44 formed in the face of the upper joint member 45. Disposed eccentrically of its pivotal axis H on lever 42is a. stop formation in the preferred form of an" embossed projection fl-iwhich rides in the spiral groove "during rotative movement of the joint members and, asit works Irom the outer toward the inner convolutlons, swings the arm 42 to the limit oi its movement in slot ll,

- projection l8 constituting, as a part of structure the intervening body portion 28, the override beyond a complete or 360-degree turn would not be permitted; however, it will be observed in Fig. 3 that the slot 3! is of appreciably greater length than that of the intervening body portion 28 between the ends of the main groove, and therefore the companion swivel member willbe permitted to turn beyond 360 degreesin correspondence to tions. 52 analogous to the iormations22g- -2Idethe length of the groove 30 asit exceedsthe Y length of the intervening body portion 28 or, in other terms, the distance between the terminals 1 2B- and 21. It will therefore be apparent that by lengthening the slot 30 the joint members may swing a considerable distance more than one revolution but less than two.

In Fig. 4 there is shown-a modified form of stop means, the illustration being by way of a cross section similar to the section of Fig. 3, wherein the lower swivel joint 32 is provided with a spiral groove or track 33 which is evolved scribed in view of Fig. 2. Disposed within the aligned bore portions 50b and SI!) of the joint members is'a movable stop means in the nature of a tubular bushing 53 fitted, loosely enough to turn relative toeither joint member andmaintained in the position shown by means of a pin 5| projecting inwardly from the upper swivel member opposite the upper edge of the bushing,

' and by means of a pin 55 projecting inwardly from the lower swivel member 5| andinto a circumferentially extending notch 56 cut into the lower edge of the bushing.

The pins 54 and 55 constitute stop means on y 51 is against;the;iert.smootthe lug e I H inflg; 7,"throughnearly 360-de r S 90a posi ,jsi'tesideofthelug 5a."; j i

, to Assuming that the' bushi ng or I means-53112.5 not rotated fromflitsgposition' shown Y turned 'through' nearlyi asoh-e' iee i't' will beapparen be. rperrnitt'edill'n that if the bushing degrees less bined width across pi the diameter of pin:

. and a. tubular bushing'biiayis disposed inxlkth 1 bores. ofboth -swivelm the respective swivel: members; and the opposite Q z t'e'rminal edgeiportions 51 n fcons'titute'astop means -at -the lower edge oi the r- ,movablestop member;,.while the upper edge. ffl the:bushingisgprovided with ;an'- axially extendmg lugyi! adaptedflto' engage'thegstop m eans or v piniltolimit the rturn'ing'moveme'n-t of the bush Intheoperation ofthe device-oi tio'n wherethe pin 54 will b ear agani theoppo' the opposi-teisidei; bushing responsiv swiveihiember ima snorto degrees, i an'd such" m o e to v 3 e fi bers would rotate through a dista the i angulargwid-t the vdiarneterof'thj'f'pin' ems ever; by making" the {slot (56 1p 59 willinot vbe'fi .ana' 'spfi sw vel" members new n I embers; However, in-place of the lug-59 ltl' ere is in the upper end o'fgthe' oircumferentijallyspaced lbins' iliz, 158a swivel or jointr rotatable parts and 2| of Fig. 2; and the'cor responding parts 32 and 380114! and 4 5 4 and 5,"as wellfas the members andIELand 50a and 5 la lar displacement either less than or greater than "360 degrees, while theterms angular displacement or: length relate to the distance along an arc with'respect to the center for said arc. Where and 5 8 Of the notch movable s-top provided fa Din-59a seated ulshin'g" withia pair of;

, h o o sides of the nn 5511.; 011* the. lowerflsi e o'i' the bushing. Thisarrang'ement operates i'niexactlyy r iin Figs. 7 and 9;: 'Where-j-theterm' rotatable'is=used, it is intended to-convey anguf fterlninal 34 "is-1e the claims refer to a certain orpredetermined' distance or override, such'distance is intended to be determined in the device of Fig. 3 by the angularflength oi, theslot 30 in excess over the angular distance across the body portion 28 between the stop means afiorded by'the terminals 26 and 21 of the main slot 25. This override distance may be determined in conjunction with the'embodiments of Figs. 4 and'5 by the angular distance in excess of the length of the inner con volution beyond the end 39 of the first convolution, assuming the short slot 31, of course, to communicate as far as the inner convolution. If

fthsiot; 13'1h5hhtthgd;th'ovrride om e our 1 irespondin lyshortened;regardless-of'-how far the" I tended;-'beyond the terminal 39 I in the nature of inith'e course iof' its inward evolution" lnlthe device ofxFig. 5, the predetermined or certain override distance isto be determined in fth e-same manner asydescribed in; view of Fig. 4, i-withlthe difference that it must be assumed that Y j ithe" slotkljtis wideenough to permit the arm 42 "beapparen t :th'at-rthe upper cswive member. 59f] I I a may; be turn'ed from aposition. in .which' the pin projection it? follow the inwardly; curvonvolutions to'the fullest extent *jiist as the heale length of the notchl stv (or the as tween pinsjld; and 58a)- 'over the angur across the pins SIaandSQa);

various advttntages andobjects "of' the inion may be accomplished" aby"-modifications he-Qparticular embodiment specifically de-- cr1bed:-herein,and tal-s intended that the ap fended 'Icl'aim-sshall include all yequivalent areme ts fairly looming within ttheir 'call,

' 'g lthusr d'escribed my invention, :what. I

nt s: 1

m mbers and stop meanspermittingirelative V, rnoun ofioverridefibeyond one complete revolu n; aid stop-means comprisingrtheprovision in. of said members of an: arcua'tegro'oveextend- 1 n n ri ly f v. mined-ildistancegiand lessjlthan 360 degrees; the

11y with said grees, said stop means comprising the provision in an axial end .ofafirst one of said swivel members of a guideway extending concentrically with H the-axis of rotation of said member an angular" distance ofless than 360 jhaving opposite terminal proximity, the companion swivel member having of said first-men ti'oned guideway,

whensaid swivel members are in assembled relation, said ball shifting to opposite ends of the second guideway for stopping engagement withone-or the other of the terminal ends of the fi rst- I ngth o'f theiislot-l must besuflicien-tto permite a1l,:3.9, to\-.follow the inner convolutions to.

1b diments; of .l igs;w7 andi-9, i s the excess in stance;ac oss,,the-Ilugwsaxanu the' pin-Sl "s new and desire:toa proteotiby"Letters' In a swivel joint,- {a hair 6% relatively rotat I said members with a predetermined 7' its} turning axis Ia prede mioanioniswivel' member'having formed there-j I a jomplementary -groove. alignedconeentri first-mentioned groove' and of a ngthgreaterg-thanthe angular;distancebetwe'enq: v. the terminal ends of saidfirst-mentioned' groove? and ,a 'stop;element disposedzito move in said giro e respohsiveflto; turning movementfof said" fmembers. and movable into position j; at v ther end of the'c'ompanion groovefor-stopping" v v mentioned groove wh'en'saidswivel members aree turnedbey ond.360 degrees either direction 7 ZQxIn iaswivel joint, a' pair of swivel-members j assembled for relative turning movement and, w-sstop' means arranged to permit movement of said i ,members a predetermined amount beyond 360 de-' degrees, said guideway ends in relativelyclo'se,

anda movable stoppingelement a ball disposed in said 'guideways joint, a pair of relatively rotat able swivel membersand means for limiting the rotative movement thereof so as to permit displacement with an override beyond 360 degrees, said stop means comprising the provision in a first one of said swivel members of a spiral groove evolved with respect to the center of rotation of said members such that opposite ends of said groove are displaced with respect to each other in a direction about said. center by a predetermined length of arc, the companion swivel member having formed therein a radially extending groove leading from the end of the outermost convolution of the spiral groove at least into the next adjoining convolution of the spiral groove, and a movable stop element disposed in said radially extending groove andthe spiral groove and movable back and forth in a radial direction to 'follow said spiral consequent upon relative rotation of said swivel members, said movable element being fully disposed in said next adjoining convolution from the outer convolution or vice versa upon the completion of 360 degrees displacement of said members, the extent of said override thereafter being determined by the angular distance remaining between the innermost end of the spiral groove and said movable stop element at the time the latter is fully moved into said next adjoining convolution as aforesaid.

r 4. In a swivel joint, a pair of relatively rotatable swivel members and means for limiting the swivel movement thereof comprising the formation in the axial end of one of said members of a spiral groove evolved with respect to the center of rotation of said member and having an inner terminal which extends a predetermined amount' in the direction of evolution toward said center beyond the outer terminal thereof, thecompanion swivel member having formed in the axial end thereof confronting said first-mentioned member a radially extending groove of a length to com municate from said outer terminal of the spiral groove-at least fully into the next adjoining convolution of said spiral groove, and a ball disposed in both grooves when said members are in assembled relation, said ball being adapted to shift to opposite ends of the radial groove responsive to rotatable movement of said members so as to be in position to engage one or the other terminals of said spiral groove to arrest rotative movement of the members after turning beyond 360 degrees from either arrested position.

5. In a swivel joint, a pair of relatively rotatable swivel members and stop means arranged to limit the rotative movementthereof to a predetermined number of revolutions or fractions thereof, said stop means comprising the provision in one axial end of a first one of said swivel members of a spiral groove evolved with respect to the turning axis of said members, said groove having outer and inner terminal ends and the inner terminal extending a predetermined angular distance toward the center of evolution beyond the outer terminal, a level pivoted on the confronting axial end of the companion swivel member with an eccentric portion arranged for movement back and forth in a direction generally toward said center, when the lever is pivoted, from a position in alignment with said outer terminal to a position .in alignment at least with the next adjoining convolution, and'means constituting a stop on said eccentric portion of the lever and disposed in said spiral groove to follow the same and effect movement of said lever in one or the other direction when said swivel members are turned in either direction whereby to dispose said stop in a position for stopping engagement with one or the other terminals of said spiral groove. 6. In a swivel joint, coacting swivel members movable coaxially one with respect to the other,

each swivel member having one face abutting a likeface of the other swivel member, a substantially annular groove formed in the abutting face of one of saidswivel members with the ends of said groove spaced with respect to each other, a corresponding groove formed in the abutting face of the other swivel member and adapted to communicate with the spaced ends of the substantially annular groove aforesaid, and a movable element disposed in said grooves whereby the movement of one of said swivel members may be limited with respect to the other swivel member.

PAUL H. IRMISCHER. 

